Escapement



Nov. 28, 1944. M. RHODES- ESCAPEMENT.

Filed Dec. 12, 1940 FIG. 2

FIG. I

FIG. 4

FIG. 3

nection with the shaft I.

Patented Nov. 28, 19.44

1 Marcus H. Rhodes, Hartford, 001111., assignor to M. H. Rhodes,Inc., Hartford, Conn, a corporation of Delaware i ApplicationDecember 12, 1940, Serial nassasss 1Claim. (01. 58-117) This invention relates. to escapements, and with regard to certain more specific features,

. to impulse escapements.

Among theseveral objects of the invention may be noted the provision of an escapement for controlling gear trains and the like which is independent in operation of the character of the finish on the escapement teeth and in which i a quiet and smoothly acting recessive wiping contact is attained; the provision of an escapeprovision of escapement apparatus which is characterized by quietness and a large angle of acment which may be made at less cost; and the tion of the balance staff. Other objects will be in part obvious and in part pointed out hereinafter.

The invention accordingly comprises the elements and combinations of elements, features of construction, and arrangements of parts which will be exemplified in the structures hereinafter described, and the scope of the application of which will be indicated in the followingclaims.

In the accompanying drawing, in which are illustrated several of various possible embodiments of the invention,

33 (Fig. 2) to move 21 counterclockwise, thus bringing the! braking surface 29 into position where it will be approached by an edge 45 of the succeeding tooth 43, as shown in Fig. 3. Then as said edge 45 of the succeeding tooth 43 engages said braking surface 29, counterclockwise motion is resisted. The tooth tends to spring. back or function resiliently so that quiet action is attained. This result is aided by, .thefaot that i the end of the tooth is long and fiat. The defle'ction due to springiness is exaggerated in Fig. 3 but there is deflection.

The triangular shape of the plane of each of the teeth 43 provides "the outer relatively long edge 45 which is parallel to the axis of the wheel, and also provides at the inner apex a Fig. 1 is an end view of an escapement wheel of the invention;

Fig. 2 is an end view of the wheelof Fig. 1,

showing its application to anescapement means on a balance shaft; and,

Figs. 3 and 4 are fragmentary views showing alternative positions of the parts of Fig. 2.

Similar reference characters indicate corresponding parts throughout the several views of the drawing.

The escapement wheel carried on the shaft 1 is made up as a thin central hub 4 I. The escapement teeth 43 are stamped out and formed up as shown to provide thin, flat, springing or resilient, paddle-like cantilever teeth. Since the blank from which the teeth are shaped is thin and composed of a springy material such as springy sheet metal, the teeth are likewise springy or resilient. These teeth cooperate at edges 45 with the escapement member 2! which is formed with the extension 33. and braking surface 29.

' Member -21 is located upon the balance shaft II with which is associated the balance member l3. It will be understood that a hair spring or similar spring is used in connection with the shaft H, and that a suitable driving means is used in con- Operation is as fola lows, starting with Fig. 2: i

A springing tooth 43 engages the extension point of attachment at 41 which is relatively narrower, so that maximum springing efiect i obtained. The long edge 45, as indicated in Fig. 1, admits of considerable variation in the position of the plane of the hub 4| with respect to the plane of the escapement member 21, thereby reducing the accuracy of manufacture required in this particular, and. thus reducing manufacturing cost.

Another advantage of the springing teeth is :that they approach the extension 33 with a quick action when they move from the brake surface 29, so that the counterclockwise rotation of the member 21 is accelerated promptly. The flexing ofthe teeth not only takes up shock and dissipates noise, but alsostores up energy that effects said prompt reversal of motion of the member 21. It is always desirable that the member such as 21 and the balance wheel attached thereto travel in a counterclockwise direction over as great an angle as possible, because the further this rotation proceeds the longer it takes it to occur, and correspondingly the longer it takes to return clockwise for the next release action In other words the oscillating arc of 21 is desirably increased, which delays the running down of the apparatus for a given tension of hair spring.

Another advantage of having the member 21 oscillate through as great an are as possible is to deliver as much energy as possible to the hair spring or similar spring associated with the shaft ll. Thus this hair spring is finally in a much more taut condition and better able to start the balance wheel in reverse direction (clockwise) against the friction of the next tooth 43 on the brake surface 29.

Another advantage of the invention is that the sliding action in recess is along a substantially radial line on the stall, or, along a line closely member 33 is in contactwith'a given tooth for a.

longer period of time, receives a greater impulse,

and exercises a more powerful winding action upon the hair spring, thereby making possible the advantageous results referred to. While a spiral type of vibrating hair spring may r be used, it will be understood that other springs '15 substantially parallel to the axis of the wheel may be used for the purpose of vibrating or oscillating back and forth balance staff H.

In view of the above, it "will be *seen that the several objects of the invention are achieved and other advantageous results attained. I

As many changes could be made in the above constructions Without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in An escapement wheel comprising ahu-b portion, peripherally located teeth on said hub portion, each of which teeth is characterized as a plane of resilient material, each tooth being of triangular shape with an outside edge arranged and an inner apex .forming an attachment with said hub portion.

MARCUS H. RHODES. 

